Wednesday, January 27, 2010

Announcing the First User Interface (UI) Components for Silverlight 4

Announcing the First User Interface (UI) Components for Silverlight 4

Announcing the First User Interface (UI) Components for Silverlight 4

Posted: 27 Jan 2010 01:05 PM PST

Telerik Corporation , a leading vendor of ASP.NET AJAX, Silverlight, WinForms and WPF controls and components, as well as .NET Reporting, .NET ORM, .NET CMS solutions and Web Application Testing Tools, is excited to announce RadControls for Silverlight...( read more )...(read more)

Silverlight Cream for January 27, 2010 -- #788

Posted: 27 Jan 2010 09:47 AM PST

In this Issue: Richard Waddell , Scott Barnes , Bob Bartholomay , Alex van Beek , Sergey Barskiy , Chris Klug , Microsoft Expression Blog Shoutout: All U.S. MVPs going to the Summit note that Suzanna Moran , my MVP lead, highly suggests the session at...( read more )...(read more)

The Weekly Source Code 48 - DynamicQueryable makes custom LINQ expressions easier

Posted: 27 Jan 2010 01:52 AM PST

NOTE: An alternative title to this post might be: " The Weekly Source Code 48: Making The Weekly Source Code 47 Suck Incrementally Less. " Last week I wrote a post about Dynamic Linq Query Generation in order to solve a kind of meta-programming problem. I had a site that used ASP.NET Dynamic Data and I wanted to do a LINQ query against some data. However, because I was creating a template that didn't know enough at compile time to write a proper LINQ query that could, well, compile, I needed to creating my LINQ dynamically. Be sure to hang in here with me, the awesome happens at the end. I was trying to generate effectively this at runtime Items.Select(row => row.Property).Distinct.OrderBy(colvalue => colvalue) And I succeeded...(read more)

Upcoming Balder release - 0.8.8.6

Posted: 26 Jan 2010 11:00 PM PST

Its been crazy weeks since I decided to pull 0.8.8.5, but it was for the better. The result is that the rendering speed and quality has gone up quite dramatically. The next version of Balder will be 0.8.8.6 and will contain at least the following: - Optimized...( read more )...(read more)

Precompiled Header Files in Visual Studio 2010

Posted: 26 Jan 2010 01:08 PM PST

Hello, this is Andy Rich from the Visual C++ front-end team. Today, I'll be discussing the use of precompiled header files (aka PCH files) in our new intellisense architecture.

Back in May, Boris briefly mentioned an intellisense optimization based on precompiled header technology. This post will elaborate on that comment by providing a glimpse into how Intellisense PCH files (or iPCH files) work. We've all become accustomed to precompiled headers improving build throughput, and now in Visual Studio 2010, we use the same technology to improve intellisense performance in the IDE.

The Problem with "Pre-parses"

 

The VC++ 2010 intellisense engine mimics the command-line compiler by using a translation unit (TU) model to service intellisense requests. A typical translation unit consists of a single source file and the several header files included by that source file (and the headers those headers include, etc.).  The intellisense engine exists to provide users with answers to questions, such as what a particular type is, what the exact signature of a function is (and its overloads), or what variables are available in the current scope beginning with a particular substring.

In order for the intellisense compiler to provide this information, the intellisense engine must initially parse the TU like the command-line compiler, recursively parsing all #include files listed at the top of the source file before parsing the rest of the source file.  Thanks to C++ scoping rules, we know that we can skip all method bodies except the one you might currently be in, but, other than this optimization, the rest of the translation unit must be parsed to give an accurate answer.  We refer to this as the "pre-parse."

Pre-parses are not always required, as users spend much of their time writing code inside of a local scope.  Through careful tracking of user edits, we can say whether or not the user has changed information which requires a new pre-parse.  When this happens, we throw away our old pre-parse and start again.

So, even though you aren't editing header files, they must be continually parsed as part of the pre-parse.  As a translation unit grows in size, these parses require progressively more CPU and memory resources, and will lead to a drop in intellisense performance.  Parsing is slow, and parsing a lot of information (as in a complex translation unit) can be very slow; 3 seconds is not uncommon, and that is simply too long for an intellisense response.

The PCH Model

 

Luckily, there is an optimization developed for command-line compilers that can also be applied to the intellisense compiler: pre-compiled headers (PCHs).  The PCH model presupposes that your translation units mostly share a lot of the same common includes.  You inform the compiler of this set of headers, and it builds a pre-compiled header file.  On subsequent compilations, instead of re-compiling this set of headers, the compiler loads the PCH file and then proceeds to compile the unique portion of your translation unit.

Common Headers

a.cpp

PCH

PCH

Unique includes

b.cpp

Unique includes

c.cpp

Unique includes

There are a few caveats to this model.  First, the "common" portion of your headers must be the first files compiled in each translation unit, and they must be in the same order in all translation units.  Most developers refactor their headers to have a common header file for this purpose; this is what stdafx.h in the Visual C++ project templates is intended for.

Leveraging PCH for the Intellisense Compiler

 

In general, if you have PCH set up for use with the build compiler, the intellisense compiler is able to pick up those PCH options and generate a PCH that can be used.  Because the intellisense compiler uses a different PCH format from the build compiler, separate PCH files are created for the use of the intellisense compiler.  These files are typically stored under your main solution directory, in a subdirectory labeled 'ipch'.  (Future releases may have the command-line and intellisense compilers share these PCHs, but for now, they are separate.)

The intellisense compiler can load these iPCH files to save not only parse time, but memory as well: all translation units that share a common PCH will share the memory for the loaded PCH, further reducing the working set.  So, a properly set-up PCH scheme for your solution can make your intellisense requests execute much more rapidly and reduce memory consumption.

Here are some important things to keep in mind when configuring your project for iPCH:

·         iPCH and build compiler PCH share the same configuration settings (configurable on a per-project or per-file basis through  "Configuration Properties->C/C++->Precompiled Headers").

·         The iPCH should represent the largest set of common headers possible, except for commonly edited headers.

·         All translation units should include the common headers in the same order.  This may be best configured through a single header file that includes all the other headers, with respective .cpp files including only this "master"header file.

·         You can have different iPCH files for different translation units – but only one iPCH file can be used for any given translation unit.

·         The intellisense compiler will not create a iPCH file if there are errors in it – open up the 'error list' window and look for any intellisense errors; eliminate these errors in order to get PCH working.

·         If you feel that an iPCH has somehow become corrupted, you can shut down the IDE and delete the iPCH directory.

 

 

How to read/write the new Visual C++ project properties

Posted: 26 Jan 2010 12:53 PM PST

Visual C++ 2010 introduces several new project properties and item metadata that are not accessible via the traditional VC interfaces.  Andrew Arnott discusses the new way to read and write project properties in Visual C++ 2010 using the IVCRulePropertyStorage interface here.
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